Generally, a silver halide color photographic material (hereinafter, referred to as "color photographic material") is, after imagewise-exposure, processed by the processing steps of color development, desilvering, washing, stabilization, etc. Also, a silver halide color reversal photographic material is, after imagewise exposure, processed by the processing steps of black and white development, reversal processing, color development, desilvering, washing, stabilization, etc.
In the color development step for photographic processing, exposed silver halide grains are converted into silver by being reduced with a color developing agent and at the same time, the oxidation product of the color developing agent formed reacts with couplers to form dye images.
Then, in the subsequent desilvering step, developed silver formed by the development step is oxidized into a silver salt by a bleaching agent having an oxidative action (bleach), and further the silver salt is removed from the light-sensitive layer together with remaining silver halide by a fixing agent forming a soluble silver (fix). Bleaching and fixing may be carried out independently as a bleach step and a fix step or may be carried out simultaneously as a bleach-fix (blix) step. Details of the compositions and the processing steps are described in T. H. James, The Theory of Photographic Process, 4th edition, (1977), Research Disclosure, No. 17643, pages 28 to 29, ibid., 18716, page 651, left column to right column, ibid., No. 307105, pages 880 to 881.
In addition to the foregoing fundamental processing steps, various auxiliary steps are added for the purposes of keeping the photographic and physical qualities of dye images and keeping the stability of photographic processing. For example, there are a wash step, a stabilization step, a hardening step, a stop step, etc.
With the increase of the use of mini labs for processing of color photographic materials, a quick processing service for customers has been increased.
However, ethylenediaminetetraacetic acid ferric complex salt, which is conventionally used as a bleaching agent for a bleach step and/or a blix step in processing of color photographic materials, has a fundamental fault in that the oxidative power is weak. In spite of that the improvement such as the use of a bleach accelerator (e.g., the addition of the mercapto compound described in U.S. Pat. No. 1,138,842), etc., is added. However, quick bleaching has not yet been attained.
As a bleaching agent capable of attaining quick bleaching, potassium ferricyanide, iron chloride, bromates, etc., are known. However, potassium ferricyanide can not be widely used because of environmental concerns, iron chloride can not be widely used because of its inconvenience in handling, such as the corrosion of metals, etc., and bromates can not be widely used because of the problem of instability of the processing solution.
Accordingly, a bleaching agent capable of attaining quick bleaching having a good handling property without causing the problem at discharging the waste solution has been desired. Recently, as a bleaching agent meeting such requirements, 1,3-diaminopropanetetraacetic acid ferric complex salt has been disclosed as a bleaching agent.
However, the foregoing bleaching agent has a problem in performance, such as bleach fog forming with bleaching. As a method of reducing the formation of the bleach fog, it is disclosed to add a buffer to the bleach solution as described, e.g., in JP-A-1-213657 (the term "JP-A" as used herein means an "unexamined published Japanese patent application"). However, the improvement level is not sufficiently satisfactory. In particular, since a developer having a high activity is used in quick processing wherein the color development is carried out within 3 minutes, large bleach fog occurs even in the case of using such a buffer.
Furthermore, when the processing solution having a bleaching power containing the 1,3-diaminopropanetetraacetic acid ferric complex salt is used, there occurs a problem that during storing the photographic images after processing, the formation of stain is increased.
Moreover, when continuous processing is carried out using a processing solution having a bleaching power containing the 1,3-diaminopropanetetraacetic acid ferric complex salt, the desilvering property is greatly lowered as compared with the beginning of continuous processing. Also, precipitates form in the processing solution.
The inventors found a novel processing composition having a bleaching power, as described in JP-A-3-216650, as a means for solving these problems. However, it was found that the bleaching agent described in the above-cited patent causes yellow images to be discolored after processing. It has thus been desired to provide an alternative novel processing composition having a bleaching power and a processing method using such a processing composition.